The present invention generally pertains to holders for electric pencil sharpeners, and is particularly directed to a support which can be adapted to a combined eraser-pencil pointer and provide self-actuation of the sharpener upon pencil insertion.
The prior art discloses many power operated sharpeners to be used with either wood-encased pencil types or mechanically held drawing leads. Such devices can be actuated by pressure closure of an external switch, as in R. S. Condon, U.S. Pat. No. 3,090,358 for Sharpening Device For Pencil Leads; or by pressure closure of an internal switch as in K. Mabuchi and Y. Tsuchimochi, U.S. Pat. No. 4,050,487, for Electric Sharpener.
Cost and space savings have been obtained through combination devices in which a sharpener is mounted on one end of a powered eraser. J. Goumaz, U.S. Pat. No. 2,767,686 for Pencil Lead Pointer, describes a draftspersons lead pointing device which can be utilized with a conventional electric erasing machine. The lead pointer is adapted to either the shaft end opposite the electric eraser, or to replacement of the erasing tip.
Since by nature the erasing machines are portable, the sharpener in such combination devices is used after first picking up the device. The flexible nature of a hand held support can result in erratic less precise sharpening. The extra lifting and replacement operational steps are also time consuming.